add filter for post count query in WP_Posts_List_Table

Description

I've a custom post type "products" with a custom taxonomy "manufacturers"
I've hooked the parse_query filter when fired from edit.php because I've wanted to show posts based on current user criteria (user can edit only products belong to specific manufacturers).
Everything worked as expected, except for the post count in the table header that shows total amount of posts (not a filtered count).
Digging into the code I've found that inside WP_Posts_List_Table constructor (​http://core.trac.wordpress.org/browser/trunk/wp-admin/includes/class-wp-posts-list-table.php#L59)the following code is performed: